The co-owner of Lotus Gunworks, Robert Abell told reporters that Pulse nightclub shooter Omar Mateen came in roughly five weeks before the nightclub shootings asking to buy body armor and about 1,000 rounds of ammunition. (AP Photo/Wilfredo Lee)

The co-owner of Lotus Gunworks, Robert Abell told reporters that Pulse nightclub shooter Omar Mateen came in roughly five weeks before the nightclub shootings asking to buy body armor and about 1,000 rounds of ammunition. (AP Photo/Wilfredo Lee)

A "suspicious" Omar Mateen visited a Jensen Beach gun shop in early May and asked about body armor and bulk ammunition, prompting employees to report the interaction to the FBI, according to the shop's owner.

Mateen briefly visited Lotus Gunworks in early May and requested heavy-duty body armor usually used by law enforcement, and when he was told the store doesn't carry body armor, made a phone call in a foreign language, said Robbert Abell, the shop's co-owner.

"It was just suspicious what he was requesting," Abell said. "It's very sad that we had him that close. Unfortunately nobody connected the dots and he slipped through the cracks."

Following the phone call, Mateen asked an employee — a military veteran who Abell declined to identify — whether the store sold bulk ammunition for semiautomatic rifles.

The employee declined to sell him the ammunition - the same type of ammo Mateen used when he opened fire on a crowd at an Orlando nightclub Sunday, slaying 49 people before being killed in a police shootout.

Gunman Omar Mateen had already killed several people and injured others Sunday morning, but during a lull he searched the internet for news about his one-man assault on a gay nightclub, according to the chairman of the Senate Homeland Security Committee.

Apparently using a smartphone, Mateen also...

Federal investigators called the shop in early May after the suspicious interaction was reported, but didn't pull surveillance footage, Abell said. The employee did not get Mateen's name during the encounter.

It wasn't until after the shooting that the employee connected the dots and recognized Mateen.

"After the shooting, and unfortunately only then, it was recognized that's who was in the store," Abell said. "We contacted the FBI immediately."